Elevator system



H. BERKOVITZ June 3, i969 ELEVATOR SYSTEM m@ Nm. m2

Original Filed Nov. 25, 1966 H. BERKOVITZ 3,447,637

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i I :U l l z RN mmm l i l l I llwllllllkll EN United States Patent O Westingcorpora- 9 Claims ABSTRACT F THE DISCLOSURE A master-door operator for vertically opening elevator hatchway doors in which a vertical vane mounted above and on one side of the car for movement fore and aft in response to operation of the car-door operator, engages hatchway door operating means mounted on the side wall of the hatchway at each landing. The individual hatchway door operating means are connected through pulley and chain systems to the associated bi-parting hatchway doors. The vane on the car is of sufficient length that the hatchway door at the oor adjacent the car is opened in response to operation of the car-door operator even as the car approaches the landing. A locking mechanism connected to each hatchway door operating means locks the associated hatchway door when no car is adjacent the floor but releases it upon initial horizontal movement after engagement of the vane. The upper panel of each hatchway door is mounted in a plane behind the lower panel so that the doors at adjacent closely spaced floors may be operated without interference.

This is a continuation of application Ser. No. 596,929, filed Nov. 25, 1966 and now abandoned.

This invention relates to the elevator art and has particular relationship to elevator systems in which the doors on the elevator cars and the doors on the hatchway are moved vertically. Such systems are encountered particularly in freight elevators.

In such an elevator system each elevator car moves in a hatchway which has openings at a plurality of landings at each of which the car -may stop. The elevator car is provided with door means which may be a single movable door panel or gate movable between open and closed positions, or the door means may consist of two door panels which are coupled so that they separate when the car entrance is to be opened and converge when the entrance is to be closed. Each opening in the hatchway, or hatch opening, is also provided with door means which may consist of a single panel movable upwardly or downwardly between opened and closed positions or a pair of coupled panels which separate or converge. Typically, the door means on the car is provided With a motor which is energized to open or reclose the doors. It is desirable in the interest of economy to provide facilities for driving the hatch door means from this motor drive on the car through a coupling drive rather than to provide a separate motor for each hatch door. A door operator in an elevator system in which the hatch for door means is operated by the motor for the car door means is called a master door operator.

This invention is particularly applicable to freight elevator systems of the master-door operator type in warehouses. In -many situations, the oors of a warehouse are spaced a realtively short distance which is substantially smaller than the distance over which the panels in the hatchway opening move between the opened and closed positions. In the open position the panels of the doors then overlap, and the coupling drive cannot readily include 3,447,637 Patented June 3, 1969 components which are secured to, or penetrate into, the door means in the region between the panels for the hatchway and the car panels. While there are also numerous installations in which the door for different floors do not overlap, it is desirable that the master-door operators be usable with all types of installations and the operators for non-overlapping installations must be suitable for overlapping installations. For this reason, it is necessary that the coupling drive means between the door means of the car and the hatch door means engage the hatchway panels laterally of the openings which they close.

In accordance with the teachings of the prior art, the coupling drive between the car door means and the hatch door means is provided with an arm which is moved as the car panels are lmoved between the open and closed positions. When a car is stopped at any landing, this arm engages a channel having horizontal anges which are connected to the hatch door panels. As the car door panels are moved to the open or closed position the arm engages the anges of the channel and moves the hatch door panels correspondingly to open or closed positions.

This prior art apparatus has the disadvantage that for operation of the coupling drive the car must be stopped at a precise position. If the car is stopped either above or below the position at which the arm can enter the channel. the engagement is not effected and, the proper opening and closing of the car door means cannot be carried out. The arm may also become wedged against the flanges of the channel and jam the car in the hatchway. Because the car must come to a complete stop to effect opening of the hatch door means, the opening or closing of the door means cannot be started as the car approaches or leaves a landing and the leveling of the car at a landing cannot be effectively carried out.

It is an object of this invention to overcome the above-described difficulties, and to provide an elevator system with a master door operator in which the car and the hatchway include vertically movable door means and in the operation of which it shall not be necessary that the car be stopped to actuate the hatchway door means to the open or closed position.

Another object of the invention is to provide such an elevator system with such a master door operator in the operation of which leveling of the car while the doors are being operated shall be feasible.

In accordance with this invention an elevator system is provided in which the coupling drive of the master door operator includes an interlock member typically in the form of a Igenerally vertical vane which is carried by the car and is movable in a generally horizontal direction by the drive for -the car door means. The coupling drive also includes a cooperative member in *the hatchway at each landing which may be interlocked with the vane and moved with the vane in a generally horizontal direction while permitting Vertical movement of the vane. The interlocking with each cooperative member is effected as the car approaches its landing, the vane moving generally vertically into a slot in the cooperative interlocking member. The cooperative interlocking member is coupled to the hatch door means in such a way that as it is moved by the vane in one horizontal direction or the opposite, the hatch door is opened or closed.

For a better understanding of this invention, both -as to its organization and as to its method of operation, together with additional objects and advantages thereof, reference is made to the following description taken in connection with the accompanying drawings, in which:

FIGURE 1 is a fragmental view, generally diagrammatic showing the relationship between the panels of the hatch door means and the landing access openings of an elevator system in which this invention is embodied;

FIG. 2 is an exploded view, generally diagrammatic, showing the relationship between the car door means and the hatchway door means in a system in accordance with this invention;

FIG. 3 is an isometric View of an elevator system according to this invention showing a car approaching, or leaving, a landing;

FIG. 3A is an isometric view showing the balancing mechanism for the hatch doors;

FIG. 4 is a view in elevation of the Car Door Operator and a portion of the Coupling Drive connected to the car door means drive;

FIG. 5 is an end view as seen from the right of FIG. 4 of the Car Door Operator;

FIG. 6 is a view in elevation of the Coupling Drive connected to the Hatch Door Operator;

FIG. 7 is an end view as seen yfrom the right of FIG. 5;

FIG. 8 is a top view showing the Car Door Operator, the Coupling Drive, and the Hatch Door Operator; and

FIG. 9 is a View, partly in section and partly in elevation, of the carriage of the Coupling Drive.

The distance between successive floors is relatively short, in many of the warehouses where elevator systems according to this invention are installed. As shown in FIG. l the panels 21 and 23 of each of the hatch door means, at the intermediate floors, when in the open position, extend over the hatch entrance 25 of the lloors just below or just above and overlap the adjacent panels 23 or 21 of the adjacent door means. The components of a master door operator which interconnect the car door means and the hatch door means cannot then be readily interposed between the car panels and hatchway panels 21 and 23. This invention meets this condition without including interconnections which demand that the car be stopped at each landing before the doors are opened.

The apparatus according to this invention is shown in simpliiied -form in FIGURE 2 as embodied in a system in which the car door means has a single panel or gate 27 and the hatch door means includes the panels 21 and 23. This apparatus includes a Car Door Opera'- tor, a Hatch Door Operator, and a Coupling Drive. The gate or panel 27 includes a pair of laterally extending arms 29 and 31 to which the Car Door Operator is connected. 'Ihe hatch panels 21 and 23 include lateral arms 33 and 35 to which the Hatch Door Operator is connected and lateral leveling arms 37 and 39 (see FIGURE 3A). The Coupling Drive interconnects the Car Door Operator and the Hatch Door Operator at each landing.

The Car Door Operator includes a motor 41, which may be of the usual direct-current type and which is energized from the power supply cables (not shown) available in a car 43. The motor 41 is connected through a speed-reducing system including belts 45 and 47 and pulleys 49, `51, 53 and 5S to rotate a sprocket wheel 57 that drives a chain 59 connected to one of the arms 29 extending laterally from the gate 27 of the car door means. A counterweight 61 is suspended from the end of the lchain 59 opposite to that connected to the arm 29.

On the shaft 63 of the sprocket wheel 57 there is also a drum 65 on which a cable 67 is wound. One end of the cable 67 is connected to the arm 31 extending laterally from the opposite end of the gate 27 and when the sprocket wheel 57 and its shaft `63 are rotated the chain 59 and cable 67 raise or lower the gate 27.

The Coupling Drive includes a drive sprocket wheel 71 on the shaft 63, an idler sprocket wheel 73 horizontally, inwardly away -from the entrance 25, `and a chain 75 movable horizontally on the wheels 7 1 and 73. The chain 75 carries an extending interlock member 77 in the form of a vane which projects away from the side wall of the car 43. As the sprocket wheel 57, which d drives the raising and lowering chain 59, is rotated in one direction or the other vane 77 is moved horizontally backwardly or forwardly by the horizontal movement of the chain of the Coupling Drive.

The Coupling Drive also includes at each landing a carriage 81 provided with movable jaws or drive blocks -83 and 85 dening a slot between them. The slots of the carriage `81 at the landings are aligned with the vane 77 of the car 43 which moves upwardly and downwardly along the hatchway so that as a car approaches a landing its vane 77 moves into engagement with the slot dened by the jaws 83 and 85 of the carriage 81 at the landing.

The Coupling Drive at each landing also includes a chain 87, an idler sprocket wheel y89 and a driving sprocket wheel 91. The sprocket wheels 89 and 91 are aligned horizontally and the chain 87 is movable horizontally. The carriage 81 is moved by the vane 77 and is connected to the chain 87 to move the chain as it is moved by the horizontal movement of the vane. The driving sprocket wheel 91 is rotated, rotating a stub shaft 93 on which a sprocket wheel 95 connected to a vertical chain 97 is rotated. This chain 97 is connected to the arms 33 and 35 extending from the panels 23 and 21 and when the sprocket wheel 95 is rotated the panels 21 and 23 are opened or closed. At the end opposite from the chain 97 the panels are suspended from a cable 99 which extends around a sheave 101 supported from the wall of thev hatchway (see FIGURE 3A).

Since the hatch gates 21 and 23 are driven from one end only, it is necessary that as the gates 21 and 23 are moved they be maintained level or parallel. In the practice of this invention means (not shown) is provided for resiliently supporting the gates or panels 21 and 23 in balanced relationship and level as they are moved upwardly and downwardly.

FIG. 3A shows the interlocking and level operation reeving mechanism on the hatch doors 21 and 23. The interlocking and leveling mechanism is required with the freight master operator scheme described herein because the doors 21 and 23 are driven from one side and must be kept level; and in addition the upper and lower panels 21 and 23 must not be able to be lifted or lowered from any corner if the hatch doors are latched in the closed position. Also, this mechanism makes it possible to place the lock in a position which is relatively tamper-proof or plug-proof because the lock is placed above the upper corner of the entrance 25 and against the hatch wall.

The undriven side of the upper and lower panels 21 and 23 are supported by pulley 101 from leveling arms 37 and 39. The driver of the panels are supported by sprocket wheel 95, which is attached to sprocket wheel 91. The supports are arms 33 and 35. The sprocket 91 is driven by the carriage `81 through chain 87 and is latched and interlocked.

To prevent lifting either panel 21 and 23 on the driven side, the pulley 501 is used to relate the two doors. Pulley 501 is fastened to arms 33 and 35. The continuous cable 99 and chain 97 prevents opening the panels at the driven corner because the sprocket wheel 91 is prevented from rotating since the chain 97 cannot move the carriage 81 which is latched.

The doors are maintained level by means of parallelism mechanism. Four pulleys V503, 505, 507, 509 are fastened to the lower panel 23. Pulleys 503 and 507 are reeved between lixed arms 521 and 523 and pulleys 505 and 509 are reeved between 525 and 527. The panels are thereby maintained parallel and prevented from being lifted or lowered on the undriven side when the panels are locked. To work to very small amounts of lift on the undriven side when lifting at the upper undriven panel, a pulley similar to pulley 501 could be used `on the undriven side between arms 37 and 39.

The described mechanism makes it possible to lock and drive a very wide opening economically and effec- E tively 4since it will mean using one master drive instead of two drives as is taught by the prior art.

In operation, when the car 43 approaches or recedcs from a landing, the motor 41 is energized rotating the sprocket wheel 57 connected through the pulleys 49 through 55 and belts 45 and 47 at a substantially lower speed and at the same time driving the chain '75 to which the vane 77 is connected. The rotation of the vsprocket wheel 57 causes the gate 27 to be raised or lowered. When the car 43 is near a landing the vane 77 slides into the slot 83-:85 of the carriage at the landing and as the vane 77 is moved towards the rear of the car 43 the carriage is moved with it moving the chain 87 to which it is connected. When the gates 21 and 23 are to be opened, engagement of the vane 77 and blocks 83, `85 unlocks the hatchway gates 21 and 23 at the landing. A similar operation takes place when the car `43 is receding lfrom the landing and the gates are closed and locked.

As shown in FIGS. 3 through 9 the car 43 in the practice of this invention, includes a box-like cab 109, which has an opening in the front to which access may be obtained through door means including the gate 27 which may be raised or lowered. The cab is supported on a framework including vertical Stiles 111, 112 to which a crosshead composed of channels 113 and 115 are welded or otherwise secured. The car moves along rails 117 and 119 in the form of beams of T-section extending along the hatchway. The central stiles are provided with shoes (not shown) which engage the web of the rails 117 and 119 and maintain `and guide the car along the hatchway.

Near the entrance of the cab 109 at both ends of the access opening, angles 131 and 133 extend along the inside of the cab and project `through the top of the cab (see FIGURE 3). The angle on the side of the motor 41 is formed in two parts an upper part 131 and lower coextensive part (not shown in the interest of clarity).

The lower part `is secured to the platform of the cab. The angles 131 and 133 carry flat tracks 135 and 137 for the gate 27. The gate has wooden shoes 139 and 141 which engage these tracks 135 and 137 respectively. The angle (not shown) coextensive with angle 131 carries a -shaped casting 151 through beams 153 and 155 for the `shaft 63. This casting 151 carries a generally triangular plate 157 on which the motor 41 is supported and in which the pulley 49 is journaled. This plate also carries the bearing 59 for the pulleys 51 and 53. Secured to the outside wall 161 of the cab 109, adjacent the angle 131, there is a guide 163 for the counterweight 61. The vane 77 of the Coupling Drive is movable along a track 171 in the form of an I-beam. This track 171 is supported from the channel 113 of the crosshead and from the triangular plate 157 by hexagonal spacers 173 and 175. The web 177 of the track carries the bearings 181 for the sprocket Wheels 73.

The vane 77 carries a bracket 191 with an extension 193 which engages the chain 75 and carries the vane 77 as the chain is moved (see FIGURE 2). The bracket 191 carries upper and lower shoes or guides 195 and 197 which engage and are slidable along the llanges 199 at the track 171 (see FIGURE 5).

Near its upper part the bracket 191 carries a support 201 for cams 203 and 205 which actuate limit switches 207 and 209 to operate appropriately the vane 77 and cooperate with cam rollers 211 and 213 to actuate the switches 207 and 209 in the required manner (see FIG- URE 4).

The part of the Coupling Drive which actuates the hatchway panels 21 and 23 is mounted on a supporting bracket 221 at each landing secured to rail 117 and a coopertaive supporting angle 223 secured to the walls of the hatchway opposite the portion at which the bracket 221 is secured to the rail 117 (see FIGURE 3). A track 225 for the carriage 81 which interlocks with the vane 77 is mounted between the |brackets 221 and 223. This track 225 has an angle cross-section including a rectangular guiding portion 226 from which an apron 229 extends. The apron 229 is bolted to the brackets 221 and 223 thus serving to support the track 225. The apron 229 also serves to support a bracket 230 for the sprocket wheel 89 and its bearing 231 (see FIGURE 8). A U- shaped bracket 233, which supports the bearings 235 for the sprocket wheel 95 that is connected to the hatch doors and the sprocket wheel 91 that is driven by the chain 87, is bolted to the side of the bracket 223 which is perpendicular to the track 225.

The carriage 81 includes a guide 241 which slides along the track 225 and in the form of a yoke composed of plates 243, 245 and 247 bolted together and encircling the guiding portion 226 of the track (see FIGURES 6 and 7). The plate 243 is secured to the chain 87 and it and the carriage 81 are carried by the chain. The plate 245 carries a block 251 which carries a bracket 253. This bracket 253 has a horizontal overhang from which a pair of pins 255 and 257 extend. The guide blocks 83 and 85 are pivotally mounted on the pins 255 and 257 respectively (see FIGURE 9). These guide blocks 83 and 85 have angular tips 261 and 263 and are spaced so that a generally vertical slot is formed between the corresponding sides of the tips. The blocks 83 and 85 are held in balanced relationship setting the slot at the appropriate length by a spring 265 which extends between projections 267 and 269 on the blocks.

The carriage 81 has a latch 271 which is an elongated member having a latching hook 273 and a tail 275 that is disposed in the path of a tail 277 on the guide block 83. The latch 271 is pivotally mounted on the pin 255 on which this drive block 83 is mounted and has a slot 279 permitting movement relative to the pin 257 on which is mounted. The latch 271 is urged into the locked position by a spring 281, connected at one end to a washer 283 secured to a pin 285 extending horizontally from the bracket 253. The other end of the spring 281 engages a boss 287 on the latch 271.

The bracket 291 also carries an interlock assembly Y 297 to indicate that the door means are open (see FIG- URES 6 and 7). The carriage has a second bracket 291 bolted to an extension of the track 225. This bracket 291 has an overhang from which a locking pin 293 for the in the closed position by by the hook 273 of the latch 271.

moved horizontally, moving the vane hor1zontally. The vane 77 then engages the drive block 83 pivoting this block to the position where its tail 277 engages the tail 275 on the latch 271. The hook 273 on the latch 271 is disengaged from the pin 293 and the panels 21 and 23, are permitted to open. As the vane 77 now moves the guide block 83 now moves the carriage 81 towards the rear opening the panels.

When the hatch door means is to be closed the motor 41 1s energized to drive the gate 27 in the opposite direction. The vane 77 then moves towards the forward end of the car 43 and hatchway engaging the forward drive block and causing the carriage 81 to advance towards the access opening at the landing. This causes the gates 21 and 23 at the landing to reclose. When the carriage 81 reaches its most forward position the hook 273 on the latch 271 slides over the pin 293 and is snapped into engagement with the pin by the spring 281. While a projecting vane which enters a slot is shown the structure may be reversed to include a slotted member on the car engaged by projecting means at each landing.

To aid in the understanding of this invention the following summary is presented.

This invention relates to a master-type door operator, particularly for freight elevator systems, which makes it possible to obtain pre-release of the hatch door means and level the elevator conveniently. In addition, the invention eliminates the need of a retiring cam. The master freight operator is gradually being more broadly applied to freight elevator systems just as the master-type door operator has spread to the passenger elevator systems. The drive of this invention is a positive type drive which does not depend on friction.

In the system shown in the drawings, the car-door means is of the single panel or gate type and the hatchdoor of the biparting type. Typically, the system includes a DC motor 41 coupled to the car door means through a timing belt reduction. The gate 27 on the car is driven directly through a sprocket wheel 57, which drives one side of the gate 27 and a counterweight 61 through a chain 59. The other side of the gate is raised or lowered by means of a steel cable 67 wrapped around a drum 65.

The drum 65 is driven by an extension of the shaft 63 of sprocket wheel 57. The car door means drive is coupled to the hatch-door means through a Coupling Drive including sprocket wheels 71 and '73 and chain 75. The chain is attached to a vane guide block 191 to which is fastened the vane 77. The block moves back and forth on a track 171 as the sprocket wheels 71 and 73 rotate.

The vane 77 operates to unlock and drive the hatchdoor means at each landing through a 'combined drive-` block and interlock combination on a carriage 81. This door means is driven through a sprocket wheel 95 which is connected to both panels 21 land 23. Rotating the sprocket wheel 95 in either direction raises one panel and lowers the other.

The hatch door means is driven through a smaller sprocket wheel 91 attached to the drive sprocket wheel v 95. This smaller sprocket wheel 91, a chain 87 and a reversing sprocket wheel 89 are attached to the ripper and lower shoes 243, 245 and 247 on which is mounted the combined drive-block and interlock. This unit is guided by a track 225. The vane 77 enters in between the two drive blocks 83 and 85 and moves horizontally. This unlocks the hatch-door means and drives the door means to open position. It should be noted that the vane 77 moves from ifront to back of the car freeing the lfront of the car for the movement of the vertically moving panels 21 and 23.

The advantages of a master operator are many. It reduces the number of drive elements which reduces the cost and greatly simplifies the control :cost and maintenlanee.

The advantages of this invention are:

(l) It drives the door means directlymany prior art systems include riction drive.

(2) The car can pre-open the doors while moving in another direction because the direction of car movement does not determine the direction ot door opening.

(3) The hatch door means can be held open when the car is releveling.

(4) The interlock is combined with the drive block and guide to eliminate the retiring cam.

While a preferred embodiment of this invention has been disclosed herein, many modifications thereof are feasible. This invention is not to be restricted except insofar as is necessitated by the spirit of the prior art.

I claim as my invention:

1. An elevator system including a hatchway having a doorway at each of a plurality of landings, hatchway door means for each of said doorways, a car movable in said hatchway, said car having an entranceway, car door means ttor said entranceway, a vane connected to said car door means movable therewith lfrom front to back of said car on the opening of said car door means, means supported by the 1hatchway at each landing to be engaged by sJaid vane to be moved `front to back of said hatchway by the movement of said vane, and means connected to said hatchway supported means and to said hatchway door means for opening said hatchway door means on movement of said hatchway supported means.

2. The elevator system of claim 1 including means connected to the hatchway supported means and to the lhatchway door means for locking the hatchway door means in the closed position, and also including means actuable by said hatchway supported means when it is engaged by the vane for unlocking said locking means.

3. The elevator system of claim 1 wherein the vane is in coupled relationship relative to the hatchway supported means with the car displaced an appreciable distance above and below eac-h landing so that the associated hatchway door means can be opened and remain open with a car appreciably displaced from the landing.

4. The elevator system of claim 1 wherein both the hatchway door means and the car door means iniclude vertically slidably door panels.

5. An elevator system including la hatchway having a landing at each of a plurality of levels, hatchway door means for each said landing, said hatchway door means being reciprocally movable along a iirst line of travel to close and expose doorways at each landing, a car movable in said hatchway, master door drive means mounted on said car, a master lcoupling member on said car connected to said master door drive means to be reciprocally moved along a second line of travel by movement of said master door drive means during door opening and closing, said second line of travel being at an angle to the plane described by the movement of said hatchway door means along said first line of travel, and hatchwfay door operator means connected to each hatchway door means to be coupled with said master coupling member when said car is in the vicinity of the associated landing, said hatchway door operator means being operative to convert a movement of the master coupling member in the second line of travel into hatchway door movement in the first line of travel to effect hatchway door opening and closing in response to the operation of the master door drive means.

6. The system of claim 5 wherein said first line of travel is the vertical and the hatch-way doors are biparting vertically opening doors, wherein the master coupling member is a generally vertical vane, wherein the second line of travel along which the Vane is movable by the movement of the master door drive means is generally horizontal and fore and aft with respect to the car and wherein each hatchway door operator means includes a cooperative coupling member having a generally vertical coupling means for said vane open lat the top and bottom into which said vane is coupled as the car approaches a landing.

7. The system of claim 6 wherein each hatchwlay door operator means includes in .said hatchway a first chain, means coupling the cooperative coupling member to said first chain to move said cliain generally horizontally fore and aft, a first sprocket wheel connected to said chain to be rotated thereby, a second sprocket wheel connected to said first sprocket wheel to be rotated thereby, and a. second chain connected to said se'cond sprocket wheel to be rotated therewith and @also connected to the hatchway door means to move said door means vertical- 1y.

8. The system of claim 6 wherein a plurality of hatchway door operator means includes locking means connected to the associated cooperative coupling member,

said locking means being effective to lock said associated hatchway door means in the closed position upon final horizontal movement of the cooperative coupling 9 member during door closing and being released by initial horizontal movement of the master coupling member 'against the associated cooperative coupling member during door opening.

9. The system of claim 6 wherein the first panels of each bi-parting 'vertically opening hatchway door are mounted in common vertical plane parallel to and in close proximity to the common plane of the se'cond panels of each door whereby the panels of an open hatchway door may overlap the panels of doors at adjacent closely spaced landings without interference.

References Cited UNITED STATES PATENTS 12/ 1928 Waldman 187-52 2/ 1950 Guilbert IS7-52 4/ 1953 Clift 187-60 8/ 1962 Guilbert 187-60 11/1962 Tucker 187-52 U.S. Cl. X.R. 

